Fluid mixing means



My 6, 1958 E. J. MARTIN FLUID MxxING MEANS 3 Sheets-Sheet 1 Filed Junel, 1955 w Mr ,m/Up Yy 5 n.j N55 v .u 1 .w j 2 7//////// //N////// Y d d3 ww z mm y 0.1M u H m a v vk /J {QSNx XQSQQ ZJ J/7 w f, 3%# HF w Pn.

ko Nus HTM Attorney May 6, 195s E. J. l MARTIN FLUID MIXING MEANS 3Sheets-Sheet 2 Filed June 1, 1955 wmv-Gf m mm; HEAD diz/wmf Me-@ML/ftorney May 6, 1958 E. J. MARTIN 2,83'3;530

FLUID MIXING MEANS Attorney United States Patent FLUID MIXING MEANSEdward I. Martin, Pleasant Ridge, Mich., assigner to General MotorsCorporation, Detroit, Mich., a corporation of Delaware Application June1, 1955, Serial No. 512,444

4 Claims. (Cl. 261-65) means for aspirating a liquid into a gaseousmedium.`

It is often desirable to mix a fluid such as a gas or liquid withanother fluid by means of a continuing process. One means of doing thisis to place a jet in a stream of primary fluid so that the secondaryfluid may be discharged from the jet and mixed with the primary fluid asit flows past the jet. With such an operation, it is very diicult, ifnot impossible, to obtain the exact proportions desired between thefluids. true where there is a considerable variation in the volume offluids lhandled and where it is desired to vary the proportions.Heretofore, it has been the practice to mount they jet in the stream ofprimary fluid in some fixed relation thereto and to vary the amount ofsecondary uid discharged from the jet by varying the pressure or head inthe secondary uid and/or in the primary fluid and also the size of thejet. Although this hasproved very effective in some installations it isvery difficult, if not impossible, to readily make the above enumeratedadjustments and to maintain all of the variable factors within theprescribed tolerances.

It is now proposed to provide means for mixing one fluidY with anotherfluid Iand means for readily and accurately adjusting the proportionsbetween the various fluids. f This is to be accomplished by placing ajetin a stream kof the primary fluid so that the jet may be readilymoved within this stream. As the primary fluid flows past the jet, themovement of the uid will create a pressure in the fluid in the immediatevicinity of the jet which may be termed a velocity head. Y It is a wellknown fact that the velocity of a uid is a maximum in the center of thestream and a minimum adjacent the edges thereof. If the jet can be movedtoward and away fromv the edge of the stream of primaryfluid, theVelocity head at the jet resulting from the primary flow may be readilyvaried thus affording an easy means for controlling the rate ofdischarge of the secondary fluid. It is also a well accepted lfact thatwhen an obstruction such as a tube is placed in a fluid flow, thepressure on the upstream side of the obstruction will berconsiderablylarger than on the downstream side of the obstruction. Thus if theangular disposition of the jet with respect to the stream of fuel can becontrolled, the velocity head at the jet may be varied over a widerange. Y This will also allow an easy means of .controlling the rate ofdischarge of the secondary fuel. It shouldvbe noted that the size andshape ofthe jet and also the pressures in the various fluids may remainconstant while the proportions ofthe resultant mixture are varied. Sincethe pressures,V etc., do not have to be varied, they .maybe moreaccurately controlled. Thus it will not only be possible to provide aneasily controlled mixture butl also 'an` accurately controlled one. A Y

The combustible mixture f or an" internal combustion engineof thesparkdgnited typeis normally formed by a carburetor wherein the airflows past one or more This is especially rice fuel jets so that theliquid fuel will be aspirated into the air. In order to obtain certainoperating characteristics of the engine, it is desirable to vary theamount of fuel aspirated into the air so as to provide a combustiblecharge of the desired richness. Heretofore, this has been accomplishedby means of numerous special purpose jets and choke valves that operatein conjunction with the main fuel jet. set of control means, etc., toinsure the desired operating characteristics.

It is now proposed to provide a carburetor having a jet which willsupply the fuel in any desired quantity for any desired air-fuel ratio.This jet may be mounted so as to be readily movable with .respect to theair ow so as to vary the velocity head present at the fuel jet. Inaddition, means may be provided for automatically varying the positionof the jet in response to some engine operating characteristics such asthe throttle setting or intake manifold vacuum.

In the three sheets of drawings:

Figure l is a side view of a nozzle for a fluid mixing v deviceembodying the present invention.

Figure 2 is a cross sectional view of a fluid mixing device embodying adifferent form of the present invention. Y

Figure 3 is an end view of a nozzle embodying another form of theinvention.

Figure 4r is la side View of the nozzle in Figure 3.

Figure 5 is an end View of another nozzle embodying another form of thepresent invention.

Figure 6 is a side View of the nozzle shown in Figure 5.,

Figure 7 is an end view of the nozzle illustrated in Figure l.

Figure'8 is a graph Ishowingthe operating characteristics of a nozzlesuch as shown in Figures l and 7.

Figure 9 is a fragmentary side elevational view of a carburetorembodying one form of the invention.

Figure l0 is a side View of a carburetor embodying the present inventionand having portions thereof broken away.

Figure l1 is a side view of the carburetor in Figure l0 but showing thecarburetor in a different operating condition.

Figure l2 is a fragmentary front elevational View on an enlarged scaleof a portion of the carburetor in Figure l0 with portions thereof beingbroken away.

Referring to the drawings in more detail, the present invention may beemployed wherever it is desired to mix one or more fluids with anotherfluid. This may be accomplished by employing one or more jets that aredisposed in a flow of primary fluid so that it will flow past the jet.Thus as the primary fluid flows past the jet and the secondaryuid isdischarged from the jet, the two fluids will be mixed with each other.lt is a well known fact that as a fluid flows past an object, the fluidwill build up a maximum pressure on the leading side of the object andat the same time, a minimum pressure will be built up on the trailingside thereof. The magnitude of the increase and decrease of the fluidpressure will vary with the velocity of the flow, and the pressurearound the yexterior' of the object will be somewhere between themaximum and minimum pressures depending upon the point at which thepressure is taken. Thus if a tube extends acrossv the stream of fluid sothat an orifice in the tube will be disposed in the flow, the pressurepresent at the orifice will be a function of the location of the orificeon the tube with respect to the direction of flow. Since the magnitudeof the pressure will affect the quantity of fluid discharged from theorifice, the rate at which the uid is discharged may be varied byvarying the angular disposition of the orifice with respect to the fluidow.

This results in a very complicated In order to take advantage of thiseffect, the secondary fluid nozzle shown in Figures l and 7 may beemployed. This nozzle may be a jet 10 that comprises an orfce 12 in atube 14 disposed in the primary fluid and extending transverselythereof.` Inthe present instance the orifice 12is formedin the end of anarm 16 disposed at right angles to the main body ofthe tube 14. Thusifthe inlet tov thettube 14 is connected to a source of secondary iluid,the secondary fluid may flow through the `tube 14 and out of the orifice12 and into the primary fluid wherethe two will mix with each other. TheVelocity. head or the pressure in the primary fluid adjacent the orifice12 will be a function of the angle at which the arm 16 is disposed withrespect to the direction of flow of the primary fluid. As previouslypointed out, the velocity head will be a maximum when the arm 16 extendstoward the direction of theprimary flow and a minimum when the arm 16extends with the primary fluid flow. If the angle between the arm 16 andthe primaryy fluid flow is represented by alpha, the variations in thevelocity head may be seen by reference to Figure 8. As may be seen fromthe graph, when alpha is zero, the velocity head is a maximum and asalpha increases, the velocity head decreases. Since the velocity head orprimary fluid pressure at the orifice 12 will affect the rate ofdischarge of the second-ary fluid, it

will thus be seen that the ratio between the volume of primary fluid andthe volume of secondary fluid may be readilycontrolled by theV simpleexpedient of rotating the tube 14.

As an alternative the fluid mixing device in Figure 2 may be employed.In this device the primary fluid flows througha housing 18 having apassage 2f) therethrough.`

This passage 20 `may be defined by a wall 22 having any desired shapesuch as a cylindrical one. A tube 24 may be mounted in a bushing 26 inthe wall 22 of the passage so that the outlet end of the tube 24 willform `a jet 28 disposed in the flow of primary fluid. The outlet end ofthe tube 24 may have'an orifice 30 therein through which the secondaryfluid may be discharged. In the present instance this orifice 30 is inthe end of an arm 32 projecting` from the tube 24 parallel to primaryflow. It is therefore apparent that as the primary fluid flows past thejet 28, a velocity head will be formed which will tend to aspirate thefuel from the tube `24 and form a mixture of the primary and secondaryfluids.

lt is well known that the velocity of the primary fluid will be amaximum in the center of the passage 20 while it will be substantiallyzero at the wall 22 of the passage 2t),` and that in between'thesepoints the velocity of the primary fluid will be some place betweenthese two values. i

Accordingly, if the tube 24 slides axially through the bushing 26, thejet 28 `willmove toward or away from a wall 22 of the passage `20 andthe velocity head at the jet 28 will vary. As a consequence, the volumeof secondary fuel discharged from the tube 24 will vary even though thequantity of primary fluid flow through the passage 20 remains constant.If desired, the tube 24 ray be rotated similar to that in the rstembodiment. Thus it may be seen that the proportion of the primary undsecondary fluids in the resulting mixture may be readily varied.

Another embodiment of the present invention is shown in Figures 3 and 4.This embodiment may be used where it is desired to mix severalsecondaryfluids with a pri mary fluid or where it is desired to mix only onesecondary fluid with the primary fluid. As seen in Figures 3 and 4, asupporting sleeve 34 extends into the flow of primary fluid so as to besubstantially normal to the direction thereof. A plurality of arms 36extend radially i in a plane substantially normal to the axis of thesleeve 34. Each of these tubes 38 may be connected to a separate sourceof secondary fluid so that several secondary fluids will be aspiratedfrom the jets 40 and mixed with the primary fluid. On the other hand allof the secondary tubes 38 may be connected to a single source ofsecondary fluid so that just onersecondary fluid will be mixed with theprimary fluid. By rotating the secondary jets 4f) or moving themvtowards or away from a wall of the passage, the quantities of secondaryfluid mixed into the primary fluid will be varied. It is, of course, tobe understood that the angular disposition of the various arms 36 may beadjusted so that the proper proportions of each secondary fluid will beVprovided.

yFigures 5 and 6 illustrate another embodiment of the present inventionwhich issimilar to that shown in Figures 3 and 4 for dispersing one ormore secondary fluids into a primary fluid. In this embodiment asupponing sleeve 42 projects into the stream of primary fluid flowsubstantially normal to the direction thereof. A plurality of secondaryfluid tubes 44 are disposed inside of the sleeve 42 with one end thereofbeing connected to one or more sources of secondary fluids. The oppositeends of the secondary tubes 44 have elbows 46 which project from thesleeve 42 so as to extend into thc fluid flow. The outer end of each ofthese elbows 46 may have an orifice 48 so that the secondary fluid inthe source to which the tubes 44 are connected, will be aspirated intothe primary fluid. Instead of being disposed in a plane, these elbowsare spirally disposed about the sleeve so that the angular dispositionthereof will allow proper mixing of the fluids. The sleeve 42 may bemoved in the primary llow so that the velocity head at the orifices 48will be varied to give the desired proportion of fluids in the resultantmixture.

Another embodiment of the present invention is shown in vFigures 10, l1and 12. 'In this embodiment the invention is incorporated into acarburetor '50 suitable for Iuse on taninternal combustion engine. Thiscarburetor 5t) includes a housing 52 lhaving a passage S4 extendingvertically therethrough. The upper end of the passage 54 forms an intake56 that may draw air directly from the atmosphere or `be connected to anair cleaner so as to draw filtered -air therethrough. The other end ofthe passage 54 may form an opening 58 in flange 60 on the lower end ofthe housing 52, This mounting flange may be suitable for attaching thecarburetor to the intake manifold of *the engine so that `the opening 58will communicate with the distribution passages in the manifold. Thusthe air may llow from the latmosphere or air cleaner through the inlet56, the passage 54 Iand the opening 58 into the intake manifold where itwill be distributed to the various cylinders of the engine. Although thepas sage 54 may be disposed in any position, in the present instance itis vertical so rthe air will flow downwardly therethrough.

The inlet and outlet portions 62 and 64V of the passage 54 may besubstantial-ly cylindrical with the outlet end 64 being of slightlysmaller diameter than the inlet. These two end portions 62 and 64 may'be interconnected f with each other by means of a venturi 66. Theupstream end of the venturi 66 may comprise an inwardly convergentconical portion 68 while the outlet end comprises an outwardly divergentconical portion 70. The two conical portions 68 `and 70 are in turninterconnected with each other by means of a throat 72 having a reduceddiameter of any desired shape ysuch as a cylinder. Thus as the air flowsthrough the passage 54, a zone of high velocity-l-ow pressure will becreated in the throat 72.

A throttlekvalve 74 may be provided for controlling the speed of theengine'by throttling the volume of air flowing through this passage 54and into the engine. ln the present instance the throttle valve 74 islocated in the intake portion 62 of the passage 54 and is of theso-called butterfly type wherein a disc is mounted on a shaft 78 f 5 ithat extends transversely of the passage '54. Theposition of Ithis valve74 may be controlled by rotating a lever 80 mounted on the outer vend ofthe shaft 78. If acontrol linkage 82 is lattached to the lever 80, thethrottle valve 74 may be opened by pulling the linkage 82 to the leftand closed by pushing lit to the right, as seen in Figure 10. Y

jln order to mix fuel with the air in the passage 54 and thereby form acombustible charge, a fuel jet 84, for aspirating fuel into the air, maybe disposed in the low pressure zone located in the throat 72 of theventuri 66. In lthe present instance this jet- 84 is formed 'by a tube86 that extends through a Wall of the housing 52 so that an ortiice 88inthe tube 86 will be disposed in the venturi throat 72.', The orifice`88 may be formed in the tube 86 at any desired point'. However, in thepresent instance it is in the end of an arm' 90disposed at right anglesto the rest of `the tube 86. Thus if the tube 86 is connectedl to a fuelline 92, the fuel may ow from a source of'fuel through the fuel line 92and tube 86 to the orifice 88. As the air ows through the passage 54, az-one of reduced pressure `will be formed in the throat 72 of theventuri 66 which will cause fuel to be discharged through the orifice 88and aspirate into air in the passage 54. Since the pressure drop in thethroat 72 is a funcratio between the .quantity of fuel and the quantityof l air. In order for this condition to prevail, the head of the fuelin the tube 86 should remain las nearly constant as possible.

`Since an engine is normally operating at part throttle a large majorityof time, it is preferable that the fuel jet 84 'be set to give anair-fuel ratio providing maximum economy. Thus the engine will beoperating mostly on an economical charge. However, it should be notedthat there are some engine operating conditions where it may bedesirable to employ -a considerably richer mixture than is required formost economical operation. For example, in order to obtain maximumperformance or power from the engine, a very rich mixture is desirable.Accordingly,

' the jet 84 may be arranged to give the maximum economy by the properrelationship between the air pressure at the orice, the size of theorifice 88, 'and the fuel pressure at the orifice. In order to provide aricher mixture, the fuel tube 86 may be moved so as to vary the velocityhead present at the orifice 88. Although the jet 84 may be moved axiallyand/ or angularly, in the present embodiment it is shown `as beingrotatably mounted. As may be seen from Figure 8, the velocity head willbe a maximum when alpha is zero and the velocity head will fall olfrapidly as the angle alpha increases thereby resulting in a much richermixture. normally only desired when'the throttle is fully open, theposition of the tube 86 may 'be controlled by a linkage system 94 whichis interconnected with the throttle valve 74 so that the tube 86 will beautomatically moved to the maximum power position whenever rthe throttlevalve 74 is fully open. In the present instance this linkage 94 includesan arm 98 on the tube 86 that is adapted to be rotated by the shaft 78and move the fuel jet 84 a corresponding amount Iand a lost motionmechanism 100 to allow part throttle movement of the throttle valve 74without effecting the fuel jets 84 position. This lost motion mechanism100 includes a plate 102 on the throttle shaft 78 that has an arcuateslot 104 therein and a link 106 connected to the arm 98 and the plate102 by means of a pin in the slot 104. Thus a limited amount of motionof the plate 102 may occur without effecting the position of the jet 84.However, as the throttle valve 74 moves to its fully opened position,the end of the slot 104 will engage the pin and any further movement ofthe throttle valve 74 towards its fully opened position Since maximumpower is Cit will result in a corresponding movement of the link 106. Asa consequence, movement of the throttle valve 74 at or near the fullyopened position will also cause rotation of the fuel jet 84.Accordingly, the orifice 88 will zbe positioned so as to provide lthemaximum power air-fuel ratio when the throttle valve 74 is lfully open.A spring 108 may be connected to the arm 98 so as to bias the arm 98`against a stop 110 and thereby retain the jet 84 in maximum economyposition unless elfected `by the linkage 94.

Another embodiment of the present invention is illustrated in Figure 9.In this embodiment a carburetor 112 substantially the same as in thefirst embodiment is employed. That is to say, the carburetor 112includes a housing 114 having an inlet 116 and an outlet 118 which areinterconnected by means of a passage having a venturi 122 with athroat.124 of reduced diameter. The fuel jet 126 may be formed by theopen end of an elbow 128 on the end of a tube 130 connected to a surceof fuel so that fuel may be discharged into thepassage 120. The oppositeend of the tube 130 may be connected to the source of fuel. When theengine is called upon to deliver maximum power, the throttle valve 7 4will be open and the intake vacuum will be small. Thus a pressure device132 responsive to the intake manifold vacuum may be interconnected tothe fuel jet 126 by a Bowden wire 134 attached to an arm 136 on the tube130. The pressure device 132 may include a piston or diaphragm 138having one side exposed to atmospheric pressure and the other side tothe intake vacuum. Thus when the throttle valve is fully closed, themanifold vacuum will 'be high causing the diaphragm 138 and Bowden Wire134 to twist the arm 136 against the stop 140 thus insuring the jet 126being maintained in the most economical position. However, as thethrottle valve is opened the manifold vacuum will drop. As the throttlevalve .approaches the fully opened position, the vacuum will drop untilsuch time as the spring 142 will overcome the effects thereof. At thispoint the spring 142 will cause the Bowden wire 134 to rotate the arm136 and the tube 130. This will, in turn, rotate the fuel jet 126 sothat when the throttle valve is fully opened, the fuel jet 126 will havebeen rotated sufliciently to cause the maximum power air-fuel ratio tobe provided.

It is to be understood that, although the invention has been describedwith specific reference to particular embodiments thereof, it is not tobe so limited since changes and alterations therein may be made whichare Within the full intended scope of this invention as defined by theappended claims.

What is claimed is:

l. A carburetor comprising a housing having a passage extendingtherethrough, a throttle valve mounted on a shaft extending transverselyof said passage for controlling the volume of air ilow therethrough, afuel jet mounted on said housing and including a portion rotatablydisposed in said passage, said portion including an orifice fordischarging said fuel into said air, lost motion means interconnecting`said throttle valve and said fuel jet for causing said valve and saidportion to rotate together, said means including a plate on said shafthaving an arcuate slot and a link having a pin riding in said slot.

2. A carburetor comprising a housing having a passage extendingtherethrough, a throttle valve mounted on a shaft extending transverselyof said passage for controlling the volume of air flow therethrough,fuel jet means mounted on said housing and including a portion rotatablydisposed in said passage, said portion including an orifice fordischarging fuel into said passage, lost motion means interconnectingsaid throttle valve and said fuel jet means, and spring meanscooperating with the lost motion means for normally biasing said fueljet means portion to a maximum fuel economy position, said lost motionmeans being adapted to rotate said jet means portion to a maXi' mum fuelflow position as the throttle approaches wide open position. -3. Acarburetor comprising a-housing having a passage extending therethrough,a throttle valve mounted on a shaft extending transversely of saidpassage for controllingv the volume of air ow therethrough, fuel jetmeans mounted on said housing land including a portion rotatablydisposed in said passage, said portion including an orifice fordischarging fuel into, said passage, lost motion means interconnectingsaid. throttle valve andsaid fuel jet means, positive stop means, andspring means normally biasing said fuel jet means into engagement withthe stop means to `position the jet means portion for maximum fueleconomy, said lost motion means being adapted to rotate saidjet meansagainst the yforce of said springV to increase fuel ow as the throttleapproaches wide open position. t

4, A carburetor comprising a .housing having a passage extendingtherethrough, a throttle valve mounted on a shaft extending transverselyof said passage for controlling the volume of air ow therethrough, fuel`jet means mounted on said housing and including a portion rotatablydisposed in said passage, said portion including an orifice fordischarging fuel into said passage, lost motion means interconnectingsaid throttle valve and said fuel jet means, an arm, said fuel jet meansextending exteriorly of said housing and being fixed to said armintermediate the endsthereof, positive stop means dist posedy on saidhousing', and spring means connected to one end of said arm and normallybiasing the other end of said arm into `engagement with the stop meansto provide maximume'conomy fuelflow through said jet means, said lostmotion means including an arm articulated` to said one end of the armand adapted to rotate said arm against the force of said spring to movesaid jet means to increase the flow' of fuel therethrough as thethrottle approaches wide open position.

References Cited in the tile of this patent UNITED STATES PATENTS1,261,756 Britton Apr. 9,1918 1,478,152 k Voegtle Dec. 1S, 19231,711,748 lSchley. May 7, 1929 2,190,314 Firth Feb. 13, 1940 2,252,955"Woods Aug. 19, 1941 2,522,196 Rouquette Sept. 12, 1950 FOREIGN `PATENTS13,339 Great Britain July 27, 1916

